Lactone stabilizing compositions

ABSTRACT

This invention provides a novel class of compounds and compositions and synthetic methods related to lactone antioxidant 3-arylbenzofuranones. The compounds may be useful to prevent yellowing and deterioration of organic materials preferably polymers, such as polyurethane foams as one example. The lactone antioxidants may be polymeric, and may also be liquid or paste in physical form at room temperature. Although it is not necessary for its stabilizing properties, the compositions may, in some species, bear one or more reactive primary OH groups on the polymer chains. The chains may also contain oligomeric oxyalkylene ether and aliphatic ester functional groups, in one embodiment of the invention.

This application is a continuation of, and claims the benefit of thefiling date of, U.S. patent application Ser. No. 12/122,961, filed onMay 19, 2008 and issued on Oct. 13, 2009 as U.S. Pat. No. 7,601,853,which application is a continuation of and claims the benefit of thefiling date of U.S. patent application Ser. No. 11/016,171, filed onDec. 17, 2004 and issued on Jun. 24, 2008 as U.S. Pat. No. 7,390,912,each of which is hereby incorporated by reference.

FIELD OF THE INVENTION

The present invention relates to compositions comprising an organicmaterial, such as a polymer, and an oligomeric lactone for use as astabilizers. The inventive compositions may be employed forstabilization of organic materials against oxidative, thermal, orlight-induced degradation. The invention is directed to novel oligomericlactones.

BACKGROUND OF THE INVENTION

Various compositions are known that function to stabilize organicmaterials against oxidative, thermal or light-induced degradation. Suchstabilization compositions may have broad applications in thermoplasticssuch as polyolefin, thermoset resins such as polyurethanes, and coatingformulations. One problem with polyurethane foams, for example, is thatsuch foams tend to yellow after a certain period of time. Yellowing offoam products is undesirable. Such yellowing may be caused by NOx gasfading or UV radiation.

U.S. Pat. Nos. 4,325,863 and 4,338,244 to Hinsken disclose 3-arylbenzofuran-2-ones and their dimers as new class of stabilizers invarious organic polymers such as polyolefins, polyurethanes andpolyesters.

U.S. Pat. Nos. 5,367,008 and 5,369,159 and 5,428,162 to Nesvadbadisclose the preparation of various 3-(alkoxyphenyl)benzofuran-2-onesand 3-(acyloxyphenyl)benzofuran-2-one derivatives, for use as polymerstabilizers.

The prior art provides a number of relatively non-reactive, solidstabilizers. Solids are difficult to use in manufacturing processes.Solids provide difficulties in handling, migration, fogging, andblooming.

New and more effective stabilizing compounds are needed in the industry.This invention provides such compounds.

DETAILED DESCRIPTION OF THE INVENTION

Reference now will be made to the embodiments of the invention, one ormore examples of which are set forth below. Each example is provided byway of explanation of the invention, not as a limitation of theinvention. In fact, it will be apparent to those skilled in the art thatvarious modifications and variations can be made in this inventionwithout departing from the scope or spirit of the invention.

This invention provides a novel class of compounds and compositions andsynthetic methods. In one aspect of the invention, the compositions maycomprise polymeric or oligomeric lactone antioxidants, such aspoly(oxyalkylene) chain(s) substituted 3-arylbenzofuranones orpoly(caprolactone) chain(s) substituted 3-arylbenzofuranones. Theinventive lactone antioxidants may be polymeric or oligomeric, which maybe liquid or pastes in nature at room temperature. In many applications,liquid or paste forms of such compounds provide a remarkable andsurprising advantage. Although it may not be necessary for itsstabilizing properties, the compositions may bear one or more reactiveprimary —OH groups on the polymer chains. For some applications, theterminal group(s) of the polymer chain(s) is not believed to be criticalwith regard to the functioning of the polymeric lactones in stabilizercompositions. The chain(s) may also contain oxyalkylene ether andaliphatic ester functional groups or radicals.

The inventive liquid lacones polymeric/oligomeric chains may containoxyalkylene segments (such as ethylene oxide and/or propylene oxide,etc, and the EO/PO ratio can be designed as such to achieve desiredhydrophilic and/or hydrophobic properties) and/or aliphatic estersegments (hydrophobic). This affords the opportunity to “tune” thelactone antioxidants for desirable compatibility in various media suchas thermosets (polyurethane), thermoplastics (PET, PP, PS, PC and thelike), wax, aqueous systems (liquid hand soap, detergents, sunscreens,fabric softeners etc. consumer products), and coatings.

Lactones bearing unique polymeric/oligomeric chains may also becomprised of specific combination of EO/PO/aliphatic esters that arecompatible with most of the above-mentioned applications. The liquidnature of the inventive polymeric lactones provides ease of handlingduring the application process. That is, the compositions may desirablybe liquids or pastes at room temperature, making it much easier to applythe compositions in manufacturing processes. And thepolymeric/oligomeric nature of the inventive lactones provides highermolecular weight and better compatibility with application media, thusis less volatile, and less prone to migrate, bloom and plate-out.

In some applications, primary hydroxy groups are present on theinventive lactone molecules. These structures offer superior reactivityin polyurethane, PET and coating systems. Thus the polymeric lactonemolecules may be chemically attached on to the application media if suchis desirable. The inventive polymeric UV absorbers may solve or mitigatemigration, leaching, fogging, plate-out, and extraction problems, eachof which is highly undesirable.

The inventive polymeric lactone antioxidants 3-arylbenzofuranones, whenused along with other additives such as UV absorbers, otherantioxidants, and light stabilizers, may significantly reduce the gasfading (NOx) and UV radiation induced yellowing of white polyurethanefoam. The compositions may be provided in liquid form, and are reactiveinto the foam, which is a significant advantage. That is, thesecompositions are truly polymeric or oligomeric, having in someapplications polyoxyalkylene and aliphatic polyester blockcopolymer/oligomer chains.

The inventive lactone stabilizers may be liquid and polymeric. They mayprovide ease of handling, processing and metering. The inventive lactonestabilizers may bear primary —OH groups at the end of polymer chains.They may be completely reactive in polyurethane, coatings, PET, andpolycarbonate applications if such is desirable. They may provideantioxidant functions to resist undesirable extraction, migration,fogging, and leaching out of the polymer matrix.

In one application, the compounds of the invention may be described asfollows:

wherein:

R₁-R₈ are each independently selected from the group consisting of H, F,Cl, Br, I, C₁-C₂₀ alkyls, C₁-C₂₀ cycloalkyls, C₁-C₂₀ alkoxy groups,C₇-C₂₀ phenylalkyls, and phenyl groups;

A is a C₂-C₂₀ alkylene oxide group or a divalent oligomeric oxyalkyleneradical;

Z is a C₂-C₂₀ alkyl or a divalent oligomeric ester radical; and

G is an end group and is selected from the group consisting of H, C₁-C₁₀alkyls, alkyl carbonyls and aryl carbonyls.

The composition “A” recited above may comprise a divalent oligomericoxyalkylene radical, which may provide the structure:

wherein:

EO comprises ethylene oxide or a derivative thereof;

PO comprises propylene oxide or a derivative thereof;

R₉ comprises a divalent C₁-C₂₀ alkyl radical;

x, y and w are independently selected from the group consisting of: zeroand positive integers or fractions between 1 and 20; wherein

x+y+w is equal or greater than 1; and wherein

R₁₀ comprises H or a C₁-C₂₀ alkyl group.

Furthermore, the Z group may be comprised of a divalent oligomeric esterradical, having the structure:

wherein:

R₁₁ and R₁₂ are independently selected from H or C₁-C₁₀ alkyl groups;

n comprises an integer between 1 and 10; and

m comprises any positive integer or fraction between 1 and 20.

In another embodiment, a compound of the invention may also berepresented by the formula:

wherein R₁, R₃, R₅-R₈, A, Z and G are as defined above.

Still in another embodiment, a compound of the invention may also berepresented by the formula:

wherein:

-   -   R₁, and R₃ are as defined above, and    -   q is a positive integer between 1 and 20, and    -   t is a positive integer between 0 and 20, and wherein q+t is        equal to or greater than 3.

Further specifically, a compound of the invention may be represented bythe formula:

wherein q and t are as defined above.

The compounds according to the invention may be effective antioxidantswhen used alone or in combination with other conventional antioxidants,for stabilizing organic materials, for example for coatings and a largenumber of polymers. For all applications in which a liquid, oligomericand non-migration properties are highly desirable, the inventivecompounds afford advantages over conventional lactone antioxidants.These polymers may be polyurethane, polyolefin, polycarbonate,polyamide, epoxyl resin, polyethers such as polyethylene glycol,polypropylene glycol or polytetramethylene glycol, and the like.

The stabilizing compositions are incorporated into the organic materialby the conventional methods, for example in any desired phase during themanufacture of shaped products. They can, for example, be mixed in theform of a liquid, a paste, a powder with other materials, suspensions oremulsions or solutions into the polymer, which can be in the form of apowder, melt, solution, suspension or emulsion.

In stabilizing polyurethane foam in particular, the inventive compoundscan be used with the following classes of additives:

Class A: Benzotriazoles are (in general) those compounds that conform tothe structure represented as the following:

wherein R₁₃, R₁₄, and R₁₅ are independently selected from hydrogen, agroup having a formula C_(a)H_(b)N_(c)O_(d)S_(e) wherein a, b, c, d, ande are from 0 to 30, and halogen.

Class B: Hindered phenols or BHT derivatives, and related compoundstypically conform to the structure of the following:

wherein R₁₆ is selected from the group consisting of hydrogen, a grouphaving a formula C_(a)H_(b)N_(c)O_(d)S_(e) wherein a, b, c, d, and e maybe from 0 to 30, and halogen.

Class C: Secondary diphenylamines may conform to the structure of thefollowing

wherein R₁₇ and R₁₈ are individually selected from the group consistingof hydrogen, a group having a formula C_(a)H_(b)N_(c)O_(d)S_(e) whereina, b, c, d, and e are from 0 to 30, and halogen.

Class D: other conventional Lactone-based antioxidants may include thosecompounds that conform to the structure of the following:

wherein R₁₉ to R₂₇ are individually selected from the group consistingof hydrogen, a group having a formula C_(a)H_(b)N_(c)O_(d)S_(e) whereina, b, c, d, and e are from 0 to 30, and halogen.

Several examples of the synthesis and application of the invention areshown below, in written form of Examples, and in data produced forTables.

Synthetic Examples of the Invention Example 1

Two hundred seventy four grams of 2,4-di-tert-butylphenol, 165 g of4-hydroxymandelic acid and 530 ml of acetic acid were combined in a twoliter three neck round bottom flask equipped with a temperature probe,stirring apparatus and condenser. The mixture was heated to 95° C., atwhich, 2.6 g of methanesulfonic acid were added. The reaction wasallowed to proceed at 95° C. for three hours. After cooling to roomtemperature and sitting overnight, the precipitated product wascollected via filtration. This filtercake was washed several times withacetic acid until the precipitate was white. After drying in a 50° C.oven, 175 g of 5,7-di-tert-butyl-3-(4-hydroxyphenyl)benzofuran-2-oneproduct having a melting point of 189-191° C. were obtained.

Example 2

In a three liter three neck round bottom flask, a solution of 32.4 g ofsodium hydroxide in 810 ml of water was formed. With stirring, 91.6 g of5,7-di-tert-butyl-3-(4-hydroxyphenyl)benzofuran-2-one were added and themixture heated to 80° C. under a nitrogen atmosphere. Once at 80° C., 27ml of 2-chloroethanol were added and the reaction held at 80° C. for twohours. After cooling to room temperature, a solution of 99 ml ofconcentrated hydrochloric acid in 1251 ml of water was added and thereaction held again at 80° C. for an additional hour. Once cooled toroom temperature, the liquid was decanted and the remaining soliddissolved in 500 ml of methylene chloride. This solution was washed oncewith 300 ml of water. After drying the methylene chloride layer overmagnesium sulfate and stripping, 92.6 g of5,7-di-tert-butyl-3-[4-(2-hydroxy-ethoxy)-phenyl]benzofuran-2-one, alight yellow solid remained. This solid can be further recrystallizedfrom ethanol/water.

Example 3

Fifteen grams of5,7-di-tert-butyl-3-[4-(2-hydroxy-ethoxy)-phenyl]benzofuran-2-one, 13.5g of ε-caprolactone and 0.3 g of 50% hypophosphorous acid were chargedto a 100 ml three neck flask. Under a nitrogen atmosphere, the mixturewas heated to 100° C. and held for three hours. Twenty four grams ofviscous liquid product having a light yellow color were obtained.

Example 4

Three hundred grams of5,7-di-tert-butyl-3-(4-hydroxyphenyl)benzofuran-2-one, 500 g of tolueneand 3 g of lanthanum phosphate catalyst were charged into an autoclave.The reaction mixture was purged several times with nitrogen gas (to apressure of 60 PSIG) and finally pressurized to 5 PSIG of nitrogen.After heating the autoclave to 121° C., ethylene oxide was added to thereaction mixture until the pressure in the reactor reached 60 PSIG.After the pressure dropped to 30 PSIG due to consumption of ethyleneoxide, more ethylene oxide was added to the reactor in the same fashionas previously described until a total of 192 g of ethylene oxide hadbeen added. Afterwards, the reaction mixture was post-cooked for a totalof 30 minutes. Toluene was removed via vacuum stripping yielding 472 g(96%) of a light yellow viscous liquid.

Article Production and Performance Testing for Inventive LiquidPolymeric Lactone Antioxidants

a) Polyether Foam Article Formation

-   -   The inventive lactone antioxidants were incorporated with or        without other additives to produce (in one particular embodiment        of the invention) polyurethane foam in accordance with the        following formulation and procedure:

Component Amount F3022 Polyol (from Bayer)  100 grams Water 4.53 mlDABCO 33LV (catalyst, from Air Products) 0.15 ml DABCO T10 (catalyst)0.32 ml L520 Silicone (from Crompton)  1.0 mL 80/20 Toluene diisocyanate(Bayer, 112 index) 49.0 ml Reactint ® Blue X3LV as noted InventivePolymeric Lactone Antioxidants as noted Additive from Class A as notedTinuvin ® 326 Additive from Class B as noted Irganox ® 1135 Additivefrom Class C as noted Irganox ® 5057 Additive from Class D as notedIrganox ® HP 136

Upon mixture within a reaction vessel, the reaction created a “health”bubble (indicating gelation and blowing balance), and the vessel wasthen exposed to 160° C. (generated within a conventional oven tosimulate actual heat history encountered on an industrial productionlevel) for about 3 minutes allowing the material to cure to form a foambun. The resultant foam buns were then analyzed for performance, asdiscussed in details below.

b) Performance Characteristics of Polyether Foams Including InventivePolymeric Liquid Lactone Antioxidants

-   -   The white foams made in accordance with formulation and process        as described in Section a), were all tested for standard foam        performance, in terms of rise time, tack time, and bun height,        and compared with the control polyether foams either made with        conventional commercial lactone antioxidant Irganox® HP 136 or        made without additive. Measurements within 5% of the control are        considered acceptable for the finished foam product. The        measurements are summarized in Table 1.

TABLE 1 Foam Performance of Inventive or Comparative LactoneAntioxidants Sample Additive Loading Rise Time Tack Time Bun Height Foam# (Mw) (php) (minutes) (minutes) (mm) A1 N/A N/A 1.50 3 226 A2 HP-1361.0 1.54 3 230 (Mw 350.7) A3 Example 3 1.0 1.52 3 234 (Mw 724) A4Example 3 2.0 1.52 3 228 (Mw 724) A5 Example 4 1.0 1.50 3 232 (Mw 558)A6 Example 4 1.6 1.55 3 233 (Mw 558)

Additionally, the foams produced exhibited good resiliency and densitiesmeasured at about 1.5 pounds per cubit foot. Thus, the inventivepolymeric lactone antioxidants provide acceptable polyurethane foamarticles as compared with control samples.

c) Extraction Measurements From Polyurethane Foams

-   -   The polyurethane foams produced in above Section b) were        analyzed for extraction levels using the following method. The        extraction test involved cutting 1 gram of the cured foam from        the center of the sample and post-curing the cut foam for        another 20 minutes at 160° C. in a glass jar. After cooling to        room temperature, 75 grams of methanol were then added to the        glass jar that was then capped for 1 hour. The foam was then        removed and the extract solution was analyzed to detect the        percentages of the lactone antioxidants being extracted out. The        results are summarized in Table 2.

TABLE 2 Foam Extraction Tests of Inventive or Comparative LactoneAntioxidants Sample Additive Loading Extraction Foam # (Mw) (php) (%) A1N/A N/A Not detectable A2 HP-136 1.0 >96 (Mw 350.7) A3 Example 3 1.0 <5(Mw 724) A4 Example 3 2.1 <5 (Mw 724) A5 Example 4 1.0 <5 (Mw 558) A6Example 4 1.6 <5 (Mw 558)

Based on the molecular weight of these additives, 1.0 php of HP-136 ismolar equivalent to 2.1 php of inventive additive from Example 3, and1.6 php of inventive additive from Example 4. As suggested from Table 2,the inventive liquid polymeric lactone antioxidants provide significantimprovement in the foam extraction test, comparing to comparativeexamples such as commercial product HP-136.

d) Protection of Colorants from Thermal Discoloration in PolyurethaneFoam

-   -   Liquid polymeric colorant Reactint® Blue X3LV (available from        Milliken Chemical) is widely used for the coloration of        polyurethane foam, and is known to be prone to thermal        discoloration during foam article formulation. Thus, the blue        foams were made in the presence of 1 php Blue X3LV with or        without inventive and comparative lactone antioxidants, in        accordance with formulation and process similar to those as        described Section a), with the exception that after the reaction        created a “health” bubble (indicating gelation and blowing        balance), the vessel was then exposed to 185° C. (generated        within a microwave oven to simulate actual heat history        encountered on a large industrial production environment) for        about 10 min before it was exposed to 160° C. (generated by a        conventional oven) for 3 minutes to cure the foam bun. The foam        buns were sliced in half, and then compared reading at the        center of the foam bun (usually where the discoloration occurs)        in CMC for delta E with the reading at the outer section of the        foam bun (usually where no discoloration occurs). The results        are summarized in Table 3.

TABLE 3 Stabilize Reactint ® Blue X3LV from Thermal Discoloration duringPolyurethane Foam Formation Sample Loading Observation at the Foam #Additive Mw (php) Delta E center of foam bun A7 Control n/a n/a 4.6 someyellowing or (X3LV only) color loss A8 HP-136 350 1 1.8 No color changeA9 Example 3 724 1 1.9 No color change A10 Example 4 558 1 2.4 Traceyellowing or color loss A11 Example 4 558 1.5 1.4 No color change

The data in Table 3 suggested that the inventive polymeric liquidlactone antioxidants were very effective in stabilization of polymericcolorants such as Blue X3LV from thermal degradation during thepolyurethane foam production process.

e) Protection of Pure Polyol from Thermal Degradation/Yellowing DuringPolyurethane Foam Formation

-   -   Polyols are known to be very prone to oxidation. In order to        retain the physical and chemical properties, almost all        commercial polyols are protected with conventional hindered        phenol antioxidants for storage and transportation. One major        side effect of the hindered phenols is that they cause        discoloration/yellowing during polyurethane article formation        and when exposed to exhaust gas (NOx). An antioxidant which can        effectively protect the intergraty of polyols without causing        polymers such as polyurethane foam yellowing and compatible with        polyols is highly desired. In order to test the effectiveness of        the inventive polymeric lactone antioxidants, the white foams        (without adding any colorant) were made using pure polyol (no        conventional antioxidant package presence) with or without        inventive and comparative lactone antioxidants, in accordance        with formulation and process similar to those as described        Section a), with the exception that after the reaction created a        “health” bubble (indicating gelation and blowing balance), the        vessel was then exposed to 185° C. (generated within a microwave        oven to simulate actual heat history encountered on a large        industrial production environment) for about 10 min before it        was exposed to 160° C. (generated by a conventional oven) for 3        minutes to cure the foam bun. The foam buns were sliced in half,        and then compared reading at the center of the foam bun (usually        where the discoloration occurs) in CMC for delta E with the        reading at the outer section of the foam bun (usually where no        discoloration occurs). The results are summarized in Table 4.

TABLE 4 Performance of Compositions in Stabilizing Pure Polyol fromThermal Degradation/Yellowing During PU Foam Formation Sample LoadingObservation at the Foam # Additive Mw (php) Delta E foam center A12Control n/a n/a 48.1 Very yellow (Pure polyol) A13 HP-136 350 0.1 1.1 Nocolor change A14 HP-136 350 1 4.2 No color change A15 Example 3 724 0.11.5 No color change A16 Example 3 724 1 2.3 No color change A17 Example4 558 0.1 2.6 No color change A18 Example 4 558 1 2.8 No color change

Thus, the inventive polymeric liquid lactone antioxidants are veryeffective in stabilizing pure polyols from thermal degradation.

f) Protection of Polyurethane Foam Made with Pure Polyols from GasFading

-   -   In order to test the effectiveness of the inventive polymeric        lactone antioxidants in stabilizing the pure polyols from gas        (NOx) fading and comparing the performance with commonly used        conventional hindered phenol antioxidant package, the white        foams (without adding any colorant) were made using pure polyol        (no conventional antioxidant package presence), as well as        regular polyols (with the conventional stabilizer package        presences) with or without inventive and comparative lactone        antioxidants, in accordance with formulation and process similar        to those as described in Section a). After curing, the foam buns        were sliced in half, and small pieces of foam samples (diameters        of 10 cm×5 cm×2 cm) were cut from the center of each foam bun.        These foam samples were all tested under NOx gas chamber (NOx        concentration is 1 ppm) for discoloration at different exposure        time. Those foam samples exposed to different amounts of time in        NOx chamber testing were then compared reading in CMC for delta        E with respected unexposed foam samples. The results are        summarized in Table 5.

TABLE 5 Performance of Compositions in Stabilizing PU Foam FormationMade with Pure Polyol from Gas Fading Observation of Sample Loadingexposed foam Foam # Additive Mw (php) Delta E sample A19 Control 1 n/an/a 39.4 Yellow-brownish (regular polyol) A20 Control 2 n/a n/a 13.4Slight yellow (Pure polyol) A21 HP-136 350 0.1 21.5 Slight yellow A22Example 3 724 0.1 16.7 Slight yellow A23 Example 4 558 0.1 17.1 Slightyellow A24 Example 4 558 0.4 17.5 Slight yellow

It is thus clear that the inventive liquid polymeric lactoneantioxidants are superior to conventional hindered phenol antioxidantpackage in stabilizing polyol from NOx fading.

g) Reduction of Discoloration in White Polyurethane Foam

-   -   Several white foams made in accordance with formulation and        process as described in Section a), in the presence of unique        anti-discoloration additive packages consists of a UV absorber        selected from Class A, a phenolic antioxidant from Class B, a        secondary amine antioxidant from Class C and a lactone        antioxidant from Class D. The inventive liquid polymeric lactone        antioxidants are used in this unique additive package to replace        the commercial antioxidant Irgnox® HP-136 which is solid and/or        may not thoroughly miscible with polyols. The foams are made        with the inventive additive packages, as well as commercially        available additive packages, the foam buns are then sliced in        half and 2 sets of small pieces of foam samples (diameters of 10        cm×5 cm×2 cm) were cut from the center of each foam bun. One set        of these foam samples were tested under Xenon lamp and compared        the performance against UV discoloration (Xenon lamp test        according to AATCC Test No. 16-1999) and Another set of samples        were tested under NOx gas chamber (NOx concentration is 1 ppm)        for discoloration at different exposure time (gas fading test as        described in AATCC Test No. 23-1999). Those foam samples exposed        to different amounts of time under UV lamp or in the NOx chamber        were then compared reading in CMC for delta E with respected        unexposed foam samples. The inventive synergistic additive        composition packages are listed in Table 6. Also included in        Table 6 as comparatives, are control (with no additive) and        commercially available additive packages B-75 (Ciba), CS-31        (Crompton) and LS-1 (Ortegol), which are current best commercial        products in polyurethane industry for stabilization of white        polyurethane foams.

TABLE 6 Additive Compositions and Loadings in Foam Formulation AdditiveClass A Class B Class C Lactone AO package (php) (php) (php) (php) AATinuvin 326 Irgnox 1135 Irgnox 5057 HP-136 (1.5) (0.33) (0.50) (0.57) BBTinuvin 326 Irgnox 1135 Irgnox 5057 Example 3 (1.5) (0.33) (0.50) (1.18)CC Tinuvin 326 Irgnox 1135 Irgnox 5057 Example 4 (1.5) (0.33) (0.50)(0.57) DD Tinuvin 326 Irgnox 1135 Irgnox 5057 Example 4 (1.5) (0.33)(0.50) (1.16) GG Tinuvin B75 (commercially available from Ciba), loading@ 3.0 php HH CS-31 (commercially available from Crompton), loading @ 3.0php JJ LS-1 (commercially available from Goldschmidt), loading @ 3.0 phpControl 0 0 0 0

Lightfastness and gas fade test results for the inventive andcomparative sample foams are summarized in Table 7.

TABLE 7 Test Results for Inventive and Comparative Additive PackagesLightfastness Gas Fade Gas Fade Sample Additive delta E delta E delta EFoam # Package (13 hrs) (2 hrs) (4 hrs) A25 Control (N/A) 34.6 34.2 56.2A26 AA 8.7 8.8 21.2 A27 BB 7.7 10.8 27.6 A28 CC 11.6 11.8 33.4 A29 DD10.0 11.3 23.5 A30 GG 15.8 34.1 82.5 A31 HH 18.2 51.4 53.1 A32 JJ 13.537.3 53.6

Clearly, the inventive additive packages containing the inventive liquidpolymeric lactone antioxidants exhibited among the best overallperformance against discoloration of UV exposure and gas fade, comparingto state-of-the-art commercial additive packages such as GG, HH and JJ.

It is understood by one of ordinary skill in the art that the presentdiscussion is a description of exemplary embodiments only, and is notintended as limiting the broader aspects of the present invention. Theinvention is shown by example in the appended claims.

What is claimed is:
 1. A compound having the structural formula:

wherein: R₁ and R₃ are independently selected from the group consistingof H, C₁-C₂₀ alkyls, C₁-C₂₀ cycloalkyls, C₁-C₂₀ alkoxy groups, C₇-C₂₀phenylalkyls, and phenyl groups; R₂ and R₄ are each hydrogen; R₅, R₆, R₇and R₈ are independently selected from the group consisting of H C₁-C₂₀alkyls, and C₁-C₂₀ alkoxy groups; A is a C₂-C₂₀ alkylene oxide group ora divalent oligomeric oxyalkylene radical; Z is a C₂-C₂₀ alkyl or adivalent ester radical; and G is an end group selected from the groupconsisting of H, C₁-C₁₀ alkyls, alkyl carbonyls and aryl carbonyls; andwherein (i) A is a divalent oligomeric oxyalkylene radical, (ii) Z is adivalent ester radical, or (iii) A is a divalent oligomeric oxyalkyleneradical and Z is a divalent ester radical.
 2. The compound of claim 1wherein said A is a divalent oligomeric oxyalkylene radical having thestructure:

wherein: EO is ethylene oxide; PO is propylene oxide; R₉ is a divalentC₁-C₂₀ alkyl radical; x, y and w are independently selected from thegroup consisting of zero and positive integers between 1 and 20; the sumof x+y+w is equal to or greater than 1; and R₁₀ is either H or a C₁-C₂₀alkyl group.
 3. The compound of claim 1 wherein Z is a divalent esterradical, said radical having the structure:

wherein: R₁₁ and R₁₂ are independently selected from H or C₁-C₁₀ alkylgroups; n is an integer between 1 and 10; and m is any positive integerbetween 1 and
 20. 4. The compound of claim 2 wherein Z is a divalentester radical, said radical having the structure:

wherein: R₁₁ and R₁₂ are independently selected from H or C₁-C₁₀ alkylgroups; n is an integer between 1 and 10; and m is any positive integerbetween 1 and
 20. 5. A composition comprising: a) an organic materialwhich is subject to oxidative, thermal or light-induced degradation, andb) at least one compound of formula:

wherein: R₁ and R₃ are independently selected from the group consistingof H, C₁-C₂₀ alkyls, C₁-C₂₀ cycloalkyls, C₁-C₂₀ alkoxy groups, C₇-C₂₀phenylalkyls, and phenyl groups; R₂ and R₄ are each hydrogen; R₅, R₆, R₇and R₈ are independently selected from the group consisting of H C₁-C₂₀alkyl, and C₁-C₂₀ alkoxy groups; A is a C₂-C₂₀ alkylene oxide group or adivalent oligomeric oxyalkylene radical; Z is a C₂-C₂₀ alkyl or adivalent ester radical; and G is an end group selected from the groupconsisting of H, C₁-C₁₀ alkyls, alkyl carbonyls and aryl carbonyls; andwherein (i) A is a divalent oligomeric oxyalkylene radical, (ii) Z is adivalent ester radical, or (iii) A is a divalent oligomeric oxyalkyleneradical and Z is a divalent ester radical.
 6. The composition of claim 5wherein A is a divalent oligomeric oxyalkylene radical having thestructure:

wherein: EO is ethylene oxide; PO is propylene oxide; R₉ is a divalentC₁-C₂₀ alkyl radical; x, y and w are independently selected from thegroup consisting of zero and positive integers between 1 and 20; the sumof x+y+w is equal or greater than 1; and R₁₀ is H or a C₁-C₂₀ alkylgroup.
 7. The composition of claim 5 wherein Z is a divalent esterradical, said radical having the structure:

wherein: R₁₁ and R₁₂ are independently selected from the groupconsisting of H and C₁-C₁₀ alkyl groups; n is an integer between 1 and10; and m is any positive integer between 1 and
 20. 8. The compositionof claim 5 wherein said organic material comprises a synthetic polymer.